LG BD390 Service Manual page 117

ELECTRICAL TROUBLESHOOTING GUIDE
7-3. CD-ROM
CD-ROM operating is abnormal
Is there
TR LQ120 collector voltage input?
(about 1.79V, 25° C)
NO
Is there
TR LQ120 base voltage input?
(about 3.6V)
NO
Is there
TR LQ110 base voltage input?
(about 1.37V)
NO
Check the LIC501 PIN125 output.
YES
Replace the traverse assembly
and scan the pick-up barcode.
Check the main PCB pick-up
interface circuit.
YES
Check the TR LQ120.
YES
Check the TR LQ110.
4-10
NG